As the company readies its flight demonstrator, Boom Supersonic CEO Blake Scholl explains how he plans to revive supersonic air travel. 

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Rush Transcript

Joe Anselmo:

Welcome to Aviation Week's Check 6 Podcast. I'm Joe Anselmo, editorial director, and we have a special podcast for you this week. I'm joined by Senior Editor, Guy Norris, and we are at the Denver, Colorado headquarters of Boom Supersonic. Joining us is Boom Founder and CEO, Blake Scholl. Blake, Thanks for taking the time to tour us around and talk with us.

Blake Scholl:

Excited to be chatting, and great to have you here, Joe and Guy.

Joe Anselmo:

So I guess the first question for you is just why now, with supersonic? I mean, supersonic is a technology that goes back to the 1960s. And how can supersonic be sustainable? That just doesn't seem to connect for some people.

Blake Scholl:

Right. Supersonic flight's not new. In fact, this year marks the 75th anniversary of Chuck Yeager's famous flight in the Bell X-1, and of course we had the first supersonic transport between Concorde and the Tu-144 in the 1960s and ‘70s. But the first generation of supersonic transports were not economically or environmentally sustainable, and since then we've had amazing progress in airplanes. We've basically changed everything about aircraft, except how fast they fly. We have carbon fiber composites, we have turbo fanengines, we have fly-by-wire, we have digital design tools, we have now the advent of sustainable fuel. And when you put all of those things together, what we found at Boom is we can build the world's first economically and environmentally sustainable supersonic airplane. Economic sustainability means fares that passengers can afford to fly in large numbers, tens of millions of passengers, and also airlines able to operate the aircraft profitably.

Environmental sustainability is about noise and emissions, and we take that super seriously. So, Overture, thanks to improvements in aerodynamics, as well as the engines, we'll be able to meet the same most stringent noise standards as the latest generation subsonic aircraft. And from an emissions perspective, we are really on the cusp of a sustainable fuel revolution. We're seeing that we've now moved from first-generation biofuels now into second- and third- generation fuels that have better improvements in carbon reduction, better scalability of feedstocks. And then we are designing Overture, really the first airplane, first airliner that is designed around sustainable fuels, so able to use a 100% sustainable fuel without any blending, which means supersonic flight can actually be carbon neutral.

Joe Anselmo:

So you're not quite as fast as the Concorde, but you're saying you're much more sustainable, and the fares, you don't have to be a millionaire to fly in?

Blake Scholl:

That's right. So the cruise speed of Overture-1 is Mach 1.7. When we take a look at what that means for passenger flight times, it means the New York to London time is about 15 minutes slower than it would have been on Concorde. However, the fuel burn is about 40% better than what it would have been. So that's huge, and that's where we're starting with Overture-1. With Overture-2, Overture-3 we're going to push to higher speeds, greater range, better levels of affordability.

Guy Norris:

And of course, you did mention there, you touched upon the sustainable fuel aspect of this, and I think one of the things that does differentiate your plan from certainly others, is that by the time you're in service, there will be the availability of this carbon capture derived fuel. Can you talk a little bit about the relationship you've got with, I think it's Prometheus, and how you're expecting or hoping that they will be able to provide this carbon capture derived fuel for even the XB-1?

Blake Scholl:

Yes. Well, let's talk about the history of biofuels, and we'll come back and hit carbon capture based fuels specifically. First generation sustainable aviation fuel is basically biofuel. One of the most common varieties of it is built from waste oils, like waste French fry oil, and we can talk about whether it's a good thing or a bad thing, but we don't eat enough French fries to power aviation. It's expensive, the feedstocks are unscalable. One of the interesting things is when we synthesize fuel chemically, it ends up actually being more pure than fossil jet fuel. However, those impurities that are in fossil jet are actually expected by legacy airplane fuel systems and engines. And so first generation biofuels, we have to blend, say for 50/50, which then undercuts the carbon reduction advantage that you would otherwise get.

So third generation sustainable fuel is something called power-to-liquid, and it's a carbon capture based technology. Now, this might sound magical, but I've actually seen this stuff working. It works today in small scale. There are a number of different companies pursuing it, it's an exciting space, and effectively what happens is we take atmospheric carbon and we liquefy it and use an electrochemical stack to convert it into an ultrapure form of jet fuel. And then Overture is designed around not needing those impurities, meaning you don't have to blend and you can get a 100% life cycle reduction in carbon. Now, the significant thing here to understand though is what are the economics going to be, and what is the scalability going to be? There are different numbers you see depending on which sustainable fuel producer you're looking at, but we're talking an energy requirement on the order of somewhere between 75 and 100 kilowatt-hours per gallon of jet fuel.

So, run the numbers out from there. What does grid-scale solar cost? In places in the world, where is that cost curve heading? And you can see line of sight to the energy inputs and the cost of green electricity are actually going to allow this sustainable fuel to be less expensive to produce than fossil is, which is huge, less expensive. And moreover, it's built out of atmospheric carbon and sunlight, both of which we have plenty of. So what happens, and I think where a lot of people get confused with where sustainable fuel is today, versus where it's going to be, is confusion of price and cost. Price is what something costs in a marketplace when you factor in supply and demand, and today there's not much supply and there's a lot of demand. So the prices look really high, but to borrow the phrase from Wayne Gretzky, "Where's the puck going to go?" The puck goes based on where the should cost economics are going to be and where the scalable inputs are.

And with atmospheric carbon being essentially unlimited, if we run out of it, I guess we don't have the problem anymore, and then sunlight also being unlimited, then what you know is that supply is going to scale up and you're going to see long-term prices become in line with the cost of production. So you could already see billions of dollars of investment is going into scaling sustainable fuel production, and exactly how long does it take that we see prices equal jet fuel prices? That's much harder to predict, but I deeply believe it will happen because of the fundamentals.

Guy Norris:

And do you think that you will have a sufficient supply, as you hope, to power the XB-1? I should mention, of course, that's the name of your supersonic demonstrator, which will be hopefully flying later this year.

Blake Scholl:

XB-1, you're right, it's our one-third scale technology demonstrator for Overture, and we expect to do a portion of the flight test program on sustainable fuel, and I'm not worried about having that fuel.

Guy Norris:

Right. One question before I get over to Joe, is the propulsion of course is, as we mentioned earlier, the long pole in the tent often in any aircraft design, often overlooked. What is the current situation as you look towards selection of this all-important engine for the Overture?

Blake Scholl:

Yes, XB-1 flies with off-the-shelf GE engines, J85-15s actually, so it's an engine from a CF-5. And Overture, we've done a bunch of different design work. We've said that we've been working with Rolls-Royce on adaptation of Rolls-Royce engines for Overture, and we're at a really exciting point now where we know we have an airplane engine combination that works. And so how exactly did we take that forward, and what does the airplane look like? I look forward to sharing more about that later this year.

Joe Anselmo:

I just wanted to jump back to something you were talking about a little earlier, the fuel. Boom's planning on being ready to enter service by the end of the decade, 2029. Do you really think these advances in sustainable aviation fuels will be that far along by the end of this decade?

Blake Scholl:

Yes, is the short answer. And I say that based on having seen some of these plants running, knowing what it takes to scale them, and seeing where the puck is going in terms of the amount of investment that's going into that space. I don't think we know enough today to say exactly what pathway is the winning pathway, exactly what producers are the winning producers, but there is a liquid gold rush in early stage investment into SAF now, and this is the kind of thing that starts small, and then it looks big. I think we're going to see that also the development of sustainable aviation fuel looks a lot like the development of wind and solar, where, remember the early days of wind and solar, it was super expensive and there wasn't enough of it, but we found a lot of investment happened. There were some subsidies that happened along the way, and now in Saudi Arabia, solar electricity is two cents a kilowatt-hour.

Joe Anselmo:

I don't think we mentioned, but United Airlines  last June placed an order for some of your airliners. NASA is trying to solve the sonic boom problem with the X-59. You're not waiting for that, right? Your plane is initially optimized for routes over water, I guess trans-Atlantic primarily? Iis that correct?

Blake Scholl:

That's right. I come from the tech world, and there's a phrase in the tech world called minimum viable product. Meaning, the first thing you build, make it the simplest thing that is still significant enough to reach a large market. And when we look at the issue of the speed limit over land, that is ferociously difficult to repeal, both technically and politically. And so we looked at the market viability of effectively an evolution of the Concorde business model, where you would double speeds over water, and over land you have about a 20% speed advantage, kind of right under the speed of sound. It turns out there is a very large market for that airplane. We see hundreds of routes where airlines can operate profitably, where passengers will have meaningful time savings, and that turns into a market for hundreds, if not thousands of Overture airplanes. So we think it's great to get that to market quickly, and then when the technology and the regulations allow for supersonic flight over land, there's a version two product.

Guy Norris:

Joe mentioned, obviously, United's, I guess it was a breakthrough order really in terms of credibility as well for the project last year. Do you see other international customers, has that attracted more interest for the program? I guess second, as you look at expanding beyond the trans-Atlantic market to trans-Pacific, say, are you able to see the Mach 1.7 speed range working with the sort of classic airline rotations on routes, where they will be able to take advantage of that?

Blake Scholl:

There was a lot in there.

Guy Norris:

I know. Sorry.

Blake Scholl:

To be honest, though, I missed part of the question. The United order did indeed do what we hoped it would, of kickoff an increased level of interest in the airplane from airlines around the world. Ultimately, this becomes a competitive advantage. Something a lot of people don't realize is that 20% of seats at the front of the airplane, the first and business class, internationally it's more than half of airline revenue and it's about 80% of the operating profit. If you believe that passengers will switch airlines to arrive in half the time, then Overture becomes a must-have airplane for every international airline. We are at the early stages of seeing that really play out in the marketplace.

Now, your second question was about trans-Pacific operation and how that fits into airline schedules. That's one of the reasons why Mach 1.7 is really the minimum speed for this airplane. We look at not just what flight times passengers will experience, but how you build an entire schedule around the airplane. With a true doubling in crew speeds, you get better utilization on the airplane, you get better utilization of crews. There are all these other ancillary benefits. For example, crews that would otherwise timeout on a slow airplane, airlines won't need to bring a relief crew with them. Situations where crew would have to be hoteled somewhere, they can actually get home and spend the night with their families, not in the Marriott. That is not just a human benefit, it's also a real cost savings.

We've mapped this out in sort of exemplar routes around many different places in the planet. It works in the Pacific. Across the Atlantic, in some cases you can do double dailies. Across the Pacific, where you could do a one-way trip today, you can typically do two with the same crew in the same airplane in a 24 hour period. The specifics vary route to route, but in principle, that happens most of the time.

Joe Anselmo:

Walk us through the next few years. You're going to fly your demonstrator this year in Mojave, you're standing up a new production plant, you just picked Greensboro, North Carolina. You’re going to be hiring a workforce there. And then when does production begin in earnest, and when do deliveries begin?

Blake Scholl:

Absolutely. Later this year, XB-1 will take flight for the first time, and also we'll be breaking ground on the superfactory in Greensboro, North Carolina, which is where we will do final assembly for Overture. It will take about two years from groundbreaking to being ready to truly launch production. So production is slated to begin in '24, with the first airplane rolling out in '25. Begin a flight test in '26, and then we've allowed ourselves four years from start of flight test in early '26 to certification and first deliveries at the end of '29. That's about twice as long as a typical subsonic program would take, so we're building in room for learning. We want to actually hit our dates. I'm proud to say that the first two years of the Overture program, we actually have hit every major date on schedule on budget, and so we're keeping some margin in the schedule so we can keep up that track record of execution.

Guy Norris:

And when you look at the, as part of that, obviously Greensboro is the key decision, when do you expect to begin in the search for partners, or suppliers, I should say? How will that work?

Blake Scholl:

That's underway.

Guy Norris:

Is it?

Blake Scholl:

This will be a big year for supply chain for Boom.

Guy Norris:

Right, and this is aerostructures as well as systems and propulsion, everything you can think of?

Blake Scholl:

That's right. We are working through supplier partnerships kind of in priority order, but everything from aerostructure to systems, to landing gear, to avionics, to flight deck.

Guy Norris:

Right, and are people beating a path to the door to talk about this with you, or how's it working?

Blake Scholl:

We've been really surprised and excited at the reception. You alluded earlier to the order from United last year, that was a big deal as far as making it clear to the industry that this isn't just something that passengers and av geeks get excited about, but it's something that customers, the airlines get excited about, and there is going to be a real and significant market for this airplane.

Joe Anselmo:

Final question. Where is Boom in terms of funding? We saw Aerion's supersonic business jet venture flounder because of it wasn't able to attract enough money to keep going forward, and it was a pretty good venture. How comfortable are you with Boom's financial position?

Blake Scholl:

We've had a very different experience. Here's the fundamental challenge of a supersonic business jet. With the speed limit over land, it's not faster 80% of the time in real-world use case. Moreover, it comes with meaningful trade-offs. A cabin that's significantly smaller than a large subsonic business jet, less range, and yet a higher sticker price. So in the context of a customer, would you like something that's 50% more expensive than a G6, half the size of a G6, and doesn't fly as far? Oh, by the way, and it's not faster 80% of the time the way you'll actually use it.

There is a market for that product, but it's small. And I think that's the fundamental challenge, the business case for a supersonic private jet doesn't close unless you can fly supersonic over land. On the other hand, as we discussed earlier, there is a large market for Overtures without any change in regulations. For that reason, the business case closes, and for that reason, this company is very well funded.

Joe Anselmo:

Blake Scholl, thank you for taking the time to talk with Guy and me, and I hope one day to ride on one of your airplanes.

Blake Scholl:

Look forward to having you on-board.

Joe Anselmo:

Thanks so much. That is a wrap for this week's Check 6 Podcast. I am now going to turn it over to our podcast editor in London, Guy Ferneyhough, for a final note.

Guy Ferneyhough:

Thanks, Joe. Join us again next week for another episode. If you can't wait until then, check out Aviation Week's MRO Podcast, which this week focuses on the rise of Mexicana MRO. And one last request, if you're listening to us on Apple Podcasts and you want to support this podcast, please leave us a star rating or a review. Bye for now, and stay safe.